High-performance β-Ga2O3 Schottky barrier diodes and metal-semiconductor field-effect transistors on a high doping level epitaxial layer

High-performance β-Ga ₂O ₃ -based Schottky barrier diodes (SBDs) and metal-semiconductor field-effect transistors (MESFETs) are fabricated on a non-delta-doped high doping level (>10 ¹⁸ cm ⁻³) epitaxial wafer. Their electrical properties and stabilities after annealing at 200–400 °C are investigated. The ON/OFF ratios for all the SBDs are over 10 ⁸ . The ideality factors and Schottky barrier heights for the Au/β-Ga ₂O ₃ SBDs with different annealing temperatures range from 1.5 to 2.5 and from 0.8 eV to 1.0 eV, respectively. There are obvious pinch-off and saturation characteristics for the β-Ga ₂O ₃ MESFETs. The maximum drain current ( I _D,max) for the as-fabricated β-Ga ₂O ₃ MESFET is 46.8 mA/mm at anode voltage of 2.0 V. They are much higher than the previously reported values of non-delta-doped and nanobelt β-Ga ₂O ₃ MESFETs. Threshold voltages for the β-Ga ₂O ₃ MESFETs shift to the negative direction with the increase of annealing temperature. This study is meaningful to push forward the development of β-Ga ₂O ₃-based electronic devices for practical applications.